I own a 2018 Gibson Les Paul Classic. While it is a beautiful sounding guitar, the tuning stability is garbage. My playing style includes a lot of whole and 1 1/2 - sometimes 2 step bends, so it was impossible for me to get through more than one song without my instrument being noticeably out of tune. It didn't matter what type of strings or how well I lubricated the nut - my €1600 Les Paul was mostly useless outside the practice room.
The string butler was very reasonably priced, so I thought I would try it. Because of Thomann's amazing service, I had it the next day! It was easy to install on my LP and the clear acrylic doesn't take away from the appearance at all, although I think any of the other colors would look fine as well.
Pros: the guitar stays in tune as well as my Stratocasters! I can bend like crazy and stay in tune. I get to keep my beloved LP tone, and the String Butler does not take away at all from sustain or sound.
Cons: Purists will hate it because it is not "original." I am a player, not a collector, and my studio is not a museum!
Bottom line recommendation: if you have a 3x3 headstock guitar, and if you bought it to PLAY instead of look at, install a String Butler now!